Scientific and engineering practices aligned with the NGSS in the performance of secondary stage physics teachers

The study aimed to unravel the degree to which scientific and engineering practices complied with the NGSS (Next Generation Science Standards) were present in the performance of physics teachers at the secondary stage in Taif city, Saudi Arabia. The study also sought to identify the effect of the qualification and years of experience variables on the degree to which the NGSS-aligned practices were present in the performance of physics teachers. The study adopted a mixed method in applying a closed-ended questionnaire and an interview. The questionnaire comprised 44 indicators and was applied to (49) teachers who were randomly selected. The interview was applied to (6) education supervisors who were purposively selected. The results revealed that the following five practices: “asking questions and identifying problems”; “obtaining, evaluating, and communicating information”; “planning and carrying out investigations”; “analyzing and interpreting data”; and “involvement with proofs and evidence” all rated medium. The three practices, “interpretation and solutions design”; “developing and using models”; and “using mathematics and computational thinking” all rated weak. Data analysis of education supervisors’ interviews revealed that their opinions were, to an extent, concordant with the questionnaire findings. The results also revealed that graduate teachers exhibited a higher level of these practices than the teachers with just BS degrees while years of experience, as a variable, had no significant difference in teachers’ use of these practices. It was concluded that teachers of physics need to reconsider their teaching practices to be aligned with NGSS. This study can be a contribution to teachers’ professional development efforts that target the alignment of science instruction with the NGSS.


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The study adopted the mixed approach. Quantitative data were collected from (49) Secondary Stage Physics Teachers in Taif city, randomly selected, first semester 2021/2022. The qualitative data were selected from (6) physics supervisors who agreed to participate. Confidentiality and independence were made clear to participants from the onset of collecting the data. All participants (Teachers and supervisors) provided consent to participate in the study.  In addition to the preceding projects, a new document for science standards was developed in 2011 by twenty-six American States under the auspices of the National Research Council (NRC), side by side with a team of (41) members. The document dealt with science for all stages, from kindergarten till twelfth level (Achieve,, 2013), producing NGSS which is the most updated directives for reforming and developing teaching and learning science. The NGSS was designed to suit all classes from kindergarten stage to secondary (K-12). It also anticipates the future performance of students and rests on three major dimensions represented in: main ideas, scientific and engineering practices, and comprehensive concepts (Tyler & Diranna, 2018 ;Duschl & Bybee, 2014).
Because students' objectives for learning sciences in general and physics in particular have changed, science teachers of all levels need to adapt themselves to these new standards in order to achieve an actual change in their teaching practices. Therefore, educators see that teachers' qualifying programs should be developed to make teachers concentrate more on actual practice and to help them amend their practices. They should also be provided with purposeful training chances that support NGSS, and to exert an effort to make teachers change their attitude towards the practices dictated by NGSS which largely contributes to the achievement of required objectives (Severance et al., 2016 ;Bielik et al, 2021).
Among the most important objectives of NGSS and science teaching are: to make students behave and practice in a scholarly manner to gain skills of engineering design which enable them to conduct research and to solve problems they encounter throughout science study or in their actual life. Therefore, those in charge of NGSS adopted the term scientific practices instead of science processes because it combines practices and skills of whoever teaches science, besides skills of the engineer who solves problems (Harris et al., 2017). This has been done to ensure students' obtaining the correct and real mechanism by which scientific research is conducted. It is the mechanism through which scientists, like Einstein, were able to come up to their discoveries (NRC, 2012 ;Boesdorfer & Staude, 2016 ;Bielik et al., 2021).
By reviewing the official website of NGSS and the various studies that tackled scientific and engineering practices from several perspectives, with regard to measuring their range of actualizing teaching, detecting attitudes of teachers and the concerned, or to unraveling the range of students' possessing such standards at the numerous stages of learning, as discussed in the following studies: (NGSS, 2013 ;Hang & Srisawasdi, 2021 ;Pruitt, 2015 ;Malkawi & Rababah, 2018 ;Boesdorfer & Staude, 2016 ;Alshyab, 2019 ;Aboathrah, 2019 ;Stuart et al., 2021). It was made clear that there were eight practices: First, "asking questions (science) defining problems (engineering)" by which student's mind and thinking are triggered through brainstorming that they use in asking questions to identify the problem. Second practice, "developing and using models" here, the student puts a mental or practical application by which he demonstrates the phenomenon or the problem, subject of the study, and practices physics by constructing a model that helps in interpretation and prediction. He, then, is engineeringly directed via that model by which he analyzes the surrounding systems to come up to probable solutions. Third practice, Planning and carrying out investigations where the student is placed in a position that enables him to practice observation, to analyze, to conduct surveys in order to propose and test a hypothesis. Fourth practice "Analyzing and interpreting data" where the students is instructed to analyze the data and information he collected from previous practices, using diagrams, statistical analysis, data processing and interpretation. Fifth practice "involvement with pretexts, proofs and evidences" by which the student extracts pretexts and proofs to identify points of weakness and strength in order to choose the best interpretation for the phenomena, and to criticize and evaluate opinions of others. Sixth practice, "interpretations and solutions design" by which the student constructs theories to interpret such a phenomenon. He uses systematic solutions for the problem choosing the primal one from the proposed designs. Seventh practice, "obtaining, evaluating and communicating information" where the student reads scientific texts and explains them, with an aim of developing, interpreting, evaluating information sources, to secure validity. Eighth practice, "Using mathematics and computational thinking" where the student uses various mathematical and engineering skills, as math and computational thinking constitute a significant part for science and engineering. In such a case scientific models that illustrate the phenomena are presented, This presentation might be arithmetical or symbolic and provides a scientific or logical interpretation for the diverse models.
Pursuant to curricula reform, movement in general and NGSS in particular, constant comprehensive updating and developing of the teaching-education system became necessary, specifically developing performance of physics teachers. Such a development provides the teacher with necessary competences which cope with those standards. Because previous studies didn't directly and specifically tackle such practices of the teacher of physics, the current one attempts to unveil the degree of availability of scientific and engineering practices that get along with NGSS regarding the performance of physics teacher of the secondary stage.

Statement of the problem
Educators and those concerned with NGSS see that physics teachers should possess such standards in general and scientific and engineering practices in particular. (Hang & Srisawasdi, 2021 ;Bielik et al., 2021 ;Dalvi et al., 2021 ;Stuart et al., 2021 ;Malkawi & Rababah, 2018 ;Duschl & Bybee, 2014 ;Bybee, 2014 ;Tuttle et al., 2016 ;Brownstein & Horvath ,2016 ;Daisly, 2016 ;Kawasaki, 2015 ;Fulcher, 2014). Therefore, the more practice they perform on such standards, the better their teaching performance will be and that will sequentially be reflected in the performance of their students, and in achieving objectives of teaching science in a better way. Despite the latest reforms related to the manner of involving students with physics, yet there are still big challenges that confront teachers who attempt to constantly apply science practices in class (Zhang & Wong, 2021). Thus, the current study endeavors to unravel the degree of availability of scientific and engineering practices that cope with NGSS, regarding performance of physics teachers, through answering the following two questions: 1-What is the degree of availability pertaining scientific and engineering practices that cope with NGSS in the performance of physics teachers at the secondary stage? 2-Does that degree of availability in performance of those teachers vary in accordance with qualification, or years of experience?

Significance of the study
This study tackles NGSS, particularly the scientific and engineering practices, one of the modern trends and criteria that should be cared for in teaching physics. The study might also make those in charge of preparing physics teachers concentrate on preparing pre-or-in-service programs of scientific and engineering practices. It might also be beneficial for education supervisors through acquainting them with the method of assessing teachers, using a list of scientific and engineering practices that they came up to. In addition, the study might also identify training needs for such teachers.

Terms of the study NGSS:
These are American standards that provide a new vision for teaching science in America. They comprise three integrated dimensions: major ideas, scientific and engineering practices, and common concepts (Kawasaki & William, 2020). Procedurally, it is a set of standards associated with the process of teaching and learning physics at the secondary stage. They determine what students of physics should have learnt focusing on the aforementioned three dimensions. The current study particularly focuses on the scientific and engineering practices needed for teachers of physics at the stage of concern.
Scientific and engineering practices: It is the second applicable dimension of NGSS which incorporates eight practices related to science and engineering. These are: "asking questions and defining problems", "developing and using models", "Planning and carrying out investigations", "analyzing and interpreting data", "Using mathematics and computational thinking", "constructing interpretations and designing solutions", "involvement with pretexts, proofs, and evidences", and finally "obtaining, evaluating, and communicating information" (NGSS, 2013 ;Alebous, 2021 ;Jimenez-Liso et al., 2021). The study adopted these eight practices and the items contained therein which amounted to (44) students of physics at the secondary stage. These were measured through individuals' responses to the two instruments of the study set for this purpose.

Study limits and limitations
The study was confined to measuring scientific and engineering practices (contained in the instruments), being one of the three major dimensions of NGSS. It was also limited to a sample of physics teachers at the secondary stage, besides education supervisors in Taif city, first semester-2021/2022. Results were determined by the range of validity and reliability of the study.

Methodology Study approach and participants
The study adopted the mixed approach. Quantitative data were collected from (49) Secondary Stage Physics Teachers in Taif city, randomly selected, first semester 2021/2022. The qualitative data were selected from (6) physics supervisors who agreed to participate. Confidentiality and independence were made clear to participants 6 from the onset of collecting the data. All participants (Teachers and supervisors) provided consent to participate in the study.
The questionnaire comprised (8) practices and (44) items. Responses were measured in accordance to Likert's five-point scale (very high, high, medium, weak, very weak). The questionnaire was verified for validity and reliability by applying it to an exploratory sample of (15) teachers of physics. The criterion of judgement was as follows: if the mean is less than (1.36), the degree of availability is "very weak"; (1.80-2.60) weak; (2.60-3.40); medium; (3.40-4.20), high; (4.20-more) very high.
-Interview Eight open-ended questions were prepared; each one echoes the viewpoint of an education supervisor regarding the degree of availability found in the practices of teachers of physics at the secondary stage. The questions were presented to specialists in science for their opinion. To ensure validity and reliability of the interview, participating supervisors were encouraged to give correct answers and enough time was given for recording those interviews in order to be analyzed and interpreted in depth. The interpretation of the supervisor of concern was presented to him to make sure that it echoed what he meant. To ensure independence and validity of the interview, more details were given to the supervisors regarding study sample, mechanism of choice, besides interview preparation and application.

Study results
First question: " What is the degree of availability pertaining scientific and engineering practices that cope with NGSS in the performance of physics teachers at the secondary stage?" In answering this question, means and standard deviations of teachers' responses and supervisors' interviews were calculated as presented in table 1.  Table 1 shows that the general mean of degree of availability of teachers' practices was "medium", (2.69). Five practices ranked medium; these are: (asking questions and defining problems) rated first, followed by "obtaining, evaluating and communicating information" second, "Planning and carrying out investigations", third, "Analyzing and interpreting data", fourth; "involvement with pretexts, evidences, and proofs", fifth. Three practices ranked "weak". Those are: "interpretation construction and solution design" rated sixth, "developing and using models", seventh, and finally "Using mathematics and computational thinking" eighth.
Thus, one can notice that physics teachers possess a limited awareness of the significance of those practices and that was reflected in their performance. This might be attributed to some hurdles such as: absence of some components of teachers' preparing programs during the pre-or in-service period, teaching and management load, and 8 shortage of lab equipment in many schools as that impacted all practices of teachers. This result agrees with those of (Hang & Srisawasdi, 2021 ;Aboathrah, 2019 ;Alshyab, 2019 ;Malkawi & Rababah, 2018 ;Kawasaki, 2015).
The item of teachers' scientific and engineering practices might be elaborated on as follows:  Asking questions and defining problems Table 2. presents results pertaining this type of practice. Results of supervisors' interviews revealed that physics teachers ask questions in an acceptable way. They attributed such a thing to teachers' training because physical phenomena perplex students. All supervisors agreed that teachers' performance was lower than what was required from them. Such a thing negatively affected students' skills in defining scientific problems due to the improper preparation of the teachers in this domain. It is noteworthy to tell that teacher preparing programs, whether pre-or in-service, were mostly theoretical. The supervisors' attitudes agree with results of the following studies: (Alshyab, 2019 ;Aboathrah, 2019 ;Qablan, 2016 ;Brownstein & Horvath , 2016).
 Developing and using models Table 3 presents results pertaining this practice  Table 3 shows that the general mean for the availability ranked "medium", (2.51); two items ranked "medium", (no.5) and (no.6): the former rated first and the latter second. The other remaining four items ranked "weak".
Although physics necessitates using scientific predictions for the various phenomena which obligate using models, yet the findings reveal that many teachers still don't have such practice. This might be caused by teachers pre-and in-service programs that didn't help them acquire the skill of model developing, in addition to burdens assigned for them regarding teaching load, time constraints and long school curriculum.
The analysis of supervisors' interviews revealed an agreement between them and teachers' viewpoints.
Two supervisors pointed out that physics teachers are clearly weak with regard to developing and using the models in teaching; most of them still use traditional methods of teaching that depend on instructing. They also revealed that long science curriculum, besides teaching burdens and administrative works teachers are required to do are obstacles in the way of using and developing models. Despite that, the supervisors noted that physics teachers are able to understand the mechanism of how their students think. Consequently, they ask them to correlate relations between phenomena and diversified systems.
Two other supervisors pointed out that some teachers showed an improvement in using modern teaching strategies in general and models in particular as a result of using higher studies whose syllabi tackle such issues.
Such a result agrees with the findings of the following studies (Hang & Srisawasdi, 2021 ;Alshyab, 2019 ;Aboathrah, 2019) in which practicing and developing models ranked "low", but differs from the findings of the following studies (Harris et al., 2017 ;Brownstein & Horvath, 2016 ;Tuttle et al., 2016 ;Daisly, 2016 ;Kawasaki, 2015) which pointed out that teachers' performance pertaining NGSS ranked "good". Table 4 presents results pertaining this practice.  Table 4 shows that the general mean of this practice ranked "medium" (3.03). Although nature of subject matter of physics requires experimentation and scientific report writing that needs activation of surveying practice, yet teachers revealed that their practice of Planning and carrying out investigations was medium. Such a thing indicates that the practical aspect of teaching physics was still below the required level.

 Planning and carrying out investigations
It also shows that teachers. in preparing their programs, have to focus more on the practical side and to explain why scientific experiments are important for teaching physics. In addition, it is important for the student to acquire skills of data collecting via sound scientific methods and to use that correctly to explain his opinion and the occurrence of any scientific phenomenon. (Duschl & Bybee, 2014) see that teachers should ask their students to conduct scientific investigations and to provide pretexts and evidences of the results they came up to.
Interviews results revealed that all supervisors' sample confirmed that despite their conviction of the importance of planning for teaching sciences, yet the majority still use ready plans. The supervisors, thus, notice a difference between what is written in the daily or semester plan and the actual performance of the teacher in class room.
They also assure that teachers' levels in the domain of planning can't be judged via records available with them, so they ascertained that programs and incentives to practice good planning and to perfect hem are essential.
The supervisors added that many teachers don't understand the concept of surveying; consequently, the teaching method they use is the traditional one, but very few of the distinguished teachers use teaching strategies based on surveying. As a result, students' level of surveying skills is generally weak.
Findings of the questionnaire and interviews that the researcher came up to agree with results of the following studies (Alshyab, 2019 ;Aboathrah, 2019 ;Harris et al., 2017 ;Brownstein & Horvath, 2016 ;Daisly, 2016 ;Kawasaki, 2015). which revealed that teachers' performance with regard to NGSS was medium or good.
 Analyzing and interpreting data Table 5 shows results pertaining this practice.  Table 5 shows that the general mean for the availability of this practice ranked "medium" (2.74). All items ranked medium except for (no. 2) which ranked weak, rating last.
Such a result shows that some teachers still don't realize the significance of students' possessing the practice of analyzing and interpreting scientific data, besides its significance in solving problems the students encounter in their real life.
In fact, teachers need to consider its significance while preparing programs. Without this analysis, correlations, causes, system components, and understanding the physical phenomenon propitiously, could never be identified. Moreover, understanding many topics of physics requires comparisons between them and other phenomena. This entails analyzing every topic or phenomenon separately then make the required comparison. It is important that teachers should have the desire and motivation to acquaint their students with the scientific evidence on which they rely. The best way of getting such evidence is to analyze the data collected from different scientific phenomena. By analyzing results related to data analysis and interpretation of supervisors' interview, it was noted that they all confirmed that physics teachers practice this skill, but not to the required level. They attributed this to the traditional teaching method teachers still use, in addition to lack of teacher-preparing programs in general and physics teachers in particular; they still rely on ready-study plans and analyses, added to that the large number of students in classes besides teaching and administration burdens.
 Using mathematics and computational thinking. Table 6 presents results pertaining this practice.  Table 6 shows that the general mean for the availability of this practice ranked "weak", (2.29) which implies that all indicators were weak. Such a result might be attributed to the nature of physics material which obligates using math and diagrams to enable the student understand and solve problems.
In addition, teachers still suffer from model-developing skills which prevent them from relating mathematical examples to scientific models. Moreover, such a result might also be referred to lack of technical teaching aids in schools as that contributes to lack of practicing computational thinking.
By analyzing results of supervisors, it was noted that they all confirmed that physics teachers practice mathematical thinking during the teaching process, but to a small extent. Few of them assign their students scientific tasks whose solutions need math and mathematical thinking. As for computational thinking, the supervisors also pointed out that its use and practice were lacking as well. They attributed that to several reasons among which are: lack of teacher preparing programs, low level of awareness, shortage of equipment and computer sets in some schools, besides teaching and administration loads assigned for them, and for large number of students. They indicated that solving such a problem is important and can be achieved through providing teachers, who practice this activity, with moral and material incentives.
Such a result disagrees with those of the following studies: (Harris et al., 2017 ;Tuttle et al., 2016 ;Brownstein & Horvath, 2016 ;Daisly, 2016 ;Kawasaki, 2015), which revealed a satisfactory level in the performance of physics teachers with regard to NGSS. But such a result agrees with results of the following studies: (Hang & Srisawasdi, 2021 ;Alshyab, 2019 ;Aboathrah, 2019) which indicated that this practice ranked "low".  Table 7 shows that the general mean for the availability of this practice ranked "weak", (2.52), while three items ranked "medium" (no.7) rated first, followed by (no. 5) second, and (no. 3) third. Such results reflect that teachers are still below the expected level regarding student's need to possess scientific evidence to present his ideas or explain physical phenomena. The rest of items ranked "weak".

 Constructing interpretations and solution design
Although physics obligates the student to make scientific comparisons based on knowledge or scientific laws, yet teaching this subject still lacks the practices needed to achieve such a goal, because traditional methods of teaching are still being used.
In this respect, result of this study disagrees with those of the following: (Harris et al., 2017 ;Daisly, 2016 ;Kawasaki, 2015), whose results regarding the issue ranked "medium". While it is agreed with the study (Hang & Srisawasdi, 2021;Alshyab, 2019;Aboathrah, 2019), which showed a medium and low degree of science teachers' practice of constructing interpretations and designing solutions.
Analyzing supervisors' interviews revealed that the viewpoints of two of them agree with questionnaire results: teachers practice data interpretation and solution design to a great extent in teaching; they assign students tasks to design solutions for scientific problems.
Other five supervisors pointed out that the activity was not that much practiced. They attributed that to insufficient time set for class which doesn't help the teacher to do the practice, besides the shortage of teachers assigned for the practice. The supervisors added that the clearly stated designs and solutions found in teachers' guide are overlooked by them, but they never try to apply them in class. Thus, teaching physics remains traditional which solely depends on memorization. Such opinions agree with results of the following studies: (Alshyab, 2019 ;Aboathrah, 2019).
 Involvement with pretexts, evidences, and proofs Table 8. presents results pertaining this issue  Table 8 shows that the general mean for the availability of this practice, ranked "medium", (2.72), while (14) items ranked "medium" except for (no. 2) which ranked "weak".
One can notice that teachers still suffer from this practice, so some of them try to avert it by not asking students to evaluate or explain any phenomenon. Teaching and administration loads also add up to the suffering of teachers. Therefore, they still need training in the domain of constructing models and in conveying that to their students.
Results of supervisors' interview agree, to an extent, with those of the questionnaire which revealed an acceptable degree of this practice that was manifested in providing evidences in presenting scientific knowledge, even via the traditional method, though most of that is done theoretically. The practical and applicable pretexts were rarely used because of lack of suitable equipment and labs in schools, in addition to short class time, large number of students, and burdens of teaching and administration.
 Obtaining, evaluating, and communicating information. Table 9 presents results pertaining this issue  Table 9 shows that the general mean for the availability of this practice was "medium", (3.15). item (no.2) rated first ranking "very high". Such a result might be attributed to the nature of physics which necessitates using diagrams and scientific laws. Three items ranked "medium" (no. 5) rated second, (no. 4), third, and (no. 1) fourth, while (no. 3) rated last, "weak".
This indicates that teachers might not have considered that gaining and evaluating information are two essential segments of scientific work. Therefore, teachers of physics need to be convinced that the student should specify the suitable authentic source for his data and information, besides specifying the suitable mechanism to deal with such data to benefit from them in teaching or in real life. They also need to read scientific texts and encourage students to do that, silently or loudly. Students as well should concentrate on all basic scientific and integrated processes to secure education situations that enable them to practice the process clearly.
But this result disagrees with those of the following studies: (Harris et al., 2017 ;Tuttle et al., 2016 ;Daisly, 2016 ;Kawasaki, 2015) which revealed the existence of a suitable level in teachers' performance regarding NGSS.
By analyzing results of supervisors, it was noted that they all confirmed that a number of teachers never deviate from the textbook as the source of knowledge. They attributed that to administrative and technical reasons associated with time, lack of good training, and technical labs in schools. In addition, some of them don't know how to deal with sources of technical information. Yet, they pointed out that teachers request students to read readyscientific texts, but they rarely ask students to invent or produce scientific texts for the sake of designing a scientific model, or explaining a certain phenomenon. Supervisors' opinion agree with what the following studies came up to. (Alshyab, 2019 ;Hang & Srisawasdi, 2021 ;Aboathrah, 2019 ;Qablan, 2016).

Results of the second questions: "
Does that degree of availability in performance of those teachers vary in accordance with qualification, or years of experience?" Qualification "t" test was conducted to detect the significant differences between means of teachers' results pertaining qualification variable. Table 10 illustrates that.  Table 10 reveals that there are significant difference between means in favor of postgraduate teachers whose higher studies tackled modern strategies of teaching, international and national standards that include NGSS and that was well reflected in their performance. In addition, programs of higher studies in universities care about modern trends in teaching, the most significant of which at present is NGSS. Such results agree with that of (Malkawi & Rababah, 2018).

Years of experiences
One Way-ANOVA was used to analyze significant differences between means of teachers' results in accordance with years of experience variable as presented in table 11.  Table 11 shows that there are no differences with statistical significance between the two means that might be attributed to teachers' updated knowledge regarding NGSS, engineering and scientific practices pertaining difference in years of experience, or lack of in-service training associated with such standards and practices. Such results agree with those of the following studies: (Alshyab, 2019 ;Malkawi & Rababah, 2018) which revealed that there were no differences with statistical significance that might be attributed to years of experience with regard to science teachers pertaining engineering and scientific practice at the secondary stage.

Conclusion
As stated in the introduction, to implement NGSS, there is an urgent need to conduct studies on the scientific and engineering practices in teaching physics (NRC, 2012). The purpose of this study is to detect the degree of availability of eight engineering and scientific practices in the performance of physics teachers from their own perspective and the perspective of education supervisors.
Although the study was limited to the interview of (6) education supervisors, yet it took into consideration the viewpoints of the majority of physics teachers. The viewpoints of the two groups, teachers and supervisors, were concordant to a great extent.
The results revealed that teachers might not have understood or knew all scientific and engineering practices with their indications which were expected to be perfected by the students. Therefore, they were not manifested as required in their performance. Hence, teachers need sufficient support which enables them to completely understand them in a way that complies with NGSS so as to eventually be able to help their students understand them. This support can be achieved when the Ministry of Education takes into consideration such practices and indications. The Ministry also needs to train teachers and to reconsider courses offered by faculties of education in the domain of preparing physics teachers and to relate that to NGSS. There is also a need to practically apply such practices throughout pre-and in-service training of teachers.

Funding:
The researcher is grateful to Taif University, represented by the Deanship of Scientific Research, for funding this study. Research project number (34-442-1).